The general field of the present invention is hand-held stereoscopic imaging systems. Specifically, however, the invention relates to a solid state stereoscopic imaging system housed within a traditional hand-held pair of prism binoculars, which system is capable three-dimensional recording and play-back of images utilizing only one imaging sensor and one display, rather than two of each as in the prior art systems.
The use of prisms to produce enlarged images of distant objects dates back centuries, beginning, according to the history books, when Galileo first held up two prisms and gazed through them. Soon, the appropriated juxtaposed prisms were incorporated into elongated telescopes through which the viewer peered using one eye. The image presented was, of course, flat, consisting of only two dimensions. Much later, it was realized that by holding a telescope to each eye, a stereoscopic image was perceived. However, holding up two telescopes at the same time was not particularly easy, and was definitely not very convenient, thus the same technology was incorporated into what was to become the now well-known pair of hand-held binoculars.
The conventional pair of binocular is basically two small refracting telescopes held together by a frame that positions the telescopes, one to each of the viewer""s eyes. Because the binocular incorporates a separate telescope for each eye, it therefore produces a stereoscopic or three-dimensional view that adds xe2x80x9cdepthxe2x80x9d the image as perceived in the viewer""s brain.
Each refracting telescope in the binocular has an optical path defined through an objective lens at the end nearest the object being viewed, a pair of prisms appropriately arranged within the telescope""s tubular body, and an eye piece that is at the end nearest the viewer""s eye. The diameter of the objective lens determines the light-gathering power. The objective lenses (in the two adjacent telescopes) are often spaced farther apart than the eyepieces so as to enhance stereoscopic vision. Functioning as a magnifier, the eyepiece forms a large virtual image that becomes the object for the eye itself and thus forms the final image on the retina. Because of the spacing between the objective lenses, the object is xe2x80x9cviewedxe2x80x9d from a slightly different angle by each lens and therefore collects a slightly different image. Thus, the image projected onto the retina of each eye is also slightly different, and when the viewer""s brain incorporates and melds the two slightly different images received through both eyes, a unified but 3-D or stereoscopic image is perceived by the viewer.
Binoculars are now in ubiquitous usage throughout the world in many, many human endeavors from bird watching to opera-going to star-gazing. Over the years since the binocular was first introduced, many improvements have been made. Until recently, however, these improvements related mainly to refinements in the quality of the binocular""s basic component parts, such as improving the optical components to produce clearer images, increasing magnification, adding image stabilization, making them adjustable, making them more durable, making them smaller, making them more ergonomically balanced, adding low light capability, etc.
Recently, however, binoculars entered the digital age. U.S. Pat. No. 5,581,399 disclosed an improvement to the traditional binoculars by incorporating an image sensor, a first optical system (comprising the traditional lens-prisms-eyepiece arrangement), a second optical system (which digitized the signal and included some limited memory) and a display so that the viewer could choose either to view enlarged images through the first optical system in the traditional way, or to view electronically reproduced images that were previously stored in memory within the second optical system and then replayed on the display. Of particular relevance to the present invention, the device disclosed in the ""399 patent used two cameras, one in each respective optical channel, to capture separately the images received in each channel, and two internal displays, one for each channel, to produce stereoscopic playback of the stored images so that the stored information is perceived during playback by the viewer in three dimensions rather than two.
More recently still, U.S. Pat. No. 5,963,369 discloses another solid-state stereoscopic imaging system incorporated within a pair of hand-held binoculars. The device disclosed a first optical system, a second optical system, and a third optical system. The first optical system allows for magnified stereo viewing of an external object in the traditional sense. The second optical system allows for recording the magnified stereo image(s) viewed through the optics of the first optical system. The third optical system allows for reproduction of the magnified stereo image(s) captured by the second optical system. The hand-held 3-D imaging system disclosed in this patent further includes record and playback modes that are activated by switches connected to electronic processing circuitry located within the frame of the binoculars. Lastly, this patent further teaches the notion of simultaneously viewing pre-stored 3-D images while concurrently viewing the outside world. Like the ""399 patent, the ""369 patent also requires that separate systems be incorporated into each of the two telescopes in order for the captured images to be replayed stereoscopically so that viewer perceives the replayed images in three dimensions rather than two.
While these prior art devices which utilized two image capture and replay systems work well, it is well known in the art that the two systems must be perfectly aligned. Otherwise, even if there is only slight deviation between the two images being replayed, side effects such as eye strain and headaches may result.
Accordingly, there is a need in the art for a simplified system that offers all of the features and functionality of these prior art systems, but which eliminates the need for precise synchronization of the two replayed images thus reducing the threat of eye strain, headache and other detrimental results, and as an additional benefit, also reduces the cost and complexity of the system.
The present invention overcomes the problems associated with the prior art in a hand-held 3-D imaging system of the type previously described in which a pair of hand-held, twin-telescope prism binoculars are fitted with an integrated stereoscopic imaging system that can record and stereoscopically playback one or more images seen through the optics of the binoculars, and in which the stereoscopic record and playback functions are accomplished, through the use of only one imaging sensor and one display, rather than having an imaging sensor and emitter placed in the optical path of each of the two telescopes. This is accomplished by the use of optical switches that are alternated between the xe2x80x9conxe2x80x9d (transparent) and xe2x80x9coffxe2x80x9d (opaque) positions at a rate of 30 Hz or higher.
In still another, separate aspect of the present invention, 3-D viewing on a PC monitor or television can be achieved by use of an external stereoscopic eyewear to process left/right video signals, thus delivering a full-color, flicker-free 3-D image to the viewer or audience.
In yet another, separate aspect of the present invention, information can be uploaded into the viewing device. This can be useful for scene interpretation and/or image recognition.
Still another, separate aspect of the present invention, is the addition of stereo sound to any image or sequence of images stored by incorporating internally-mounted microphones within the body of the binoculars.
The device of this invention can be used for outdoor 3-D viewing, recording viewed objects in 3-D, and internal or external playback of objects recorded in 3-D. In addition, pre-stored or remote real-time images can be overlaid while stereoscopically viewing the outside world as well as stereoscopically recorded and played back. Wireless capabilities with Internet connectivity can also be added to the device of this invention.
Accordingly, it is the primary object of the present invention to provide a simplified prism binoculars with an integrated solid-state stereoscopic imaging system with only one optical receiver and transmitter common to both binocular channels. This and further objects and advantages will be apparent to those skilled in the art in connection with the drawings and the detailed description of the preferred embodiment set forth below.